If you think of mains power as the ‘gasoline’ fuelling your audio system, the AC iPurifier is the product that ensures that it’s getting a clean, super premium blend to deliver the best possible audio fidelity.

The AC iPurifier is the latest in iFi audio’s stable of ‘power products’ designed to clean-up noisy mains supplies to audio systems. But this is no ordinary mains purifier. Technologically advanced, it’s Active Noise Cancellation (ANC) circuitry can eliminate far more noise across the frequency range than other passive devices. At -40dB, the difference is as distinct as night and day.

The following diagram depicts the placement of three AC iPurifiers in one system.

Insert AC iPurifier (1) into the shared mains wall outlet.

Place AC iPurifier (2) at the first entry point.

A third AC iPurifier (3) is best located in-between the two types of power supplies.

We recommend that all linear power supplies are located after the AC iPurifier (2) but before AC iPurifier (3). Then all SMPS power supplies are located after AC iPurifier (3).

Also, the digital and analogue power sources should be in their respective groups as shown in the diagram.

I'm sure it actually cleans up the power, (i.e. removes high frequency components in the voltage waveform above 60hz) but whether there is any audible benefit to cleaner power in your system is questionable. Considering that most equipment actually converts to DC before the mains power enters any audio gear, you have to wonder. And of course it will always depend on the equipment and how it's designed. Since all competent audio engineers are aware that mains power is noisy, presumably they take effective steps to avoid introducing this type of interference to the audio signal. So my guess is that unless your amp is garbage to begin with, this won't help. And it's extremely doubtful it would flip a single bit on the output of a DAC... I'm not an expert on this subject, though. Anyone know of any tests done on this type of gear in the past?

Headphoneus Supremus

Joined:
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I'm not opposed to this being snake oil, I've got a few Pangea power cables that really did make a small difference. But the design concerns me... any video's of it being used with both US and EU Cables?

1000+ Head-Fier

And iFi is not the first company to offer such devices plug into open outlets. Never seen them at this price point. Nor do I have any idea how they differ from those similar looking competitors.

But attention of power supply makes a difference.

My question is how they work with other power conditioning products. For example I have a big ole toroidal power conditioner for my main stereo system. Would it be better to plug into its outlets or will I still see a difference if plugged into the same outlet that the power conditioner's cable is plugged into?

Power conditioning as I understand it is a process of taking whatever comes out of the wall and trying to make it close to a perfect 60hz sine wave at the original voltage. This involves either filtering out harmonics and noise from the original power, or using the mains power for powering an active power supply which then synthesizes a whole new (presumably much more pure) 60hz "signal". This one seems to be a sort of filter, so if you already have a power conditioner it will make the power incrementally cleaner, but might also be considered redundant. If the noise in your power is already at -75dB or something and you pull it down another 40dB (in the best case) then you went from practically no noise, to practically no noise again. If your power is so bad as to require two power conditioners in series, you have big problems.

500+ Head-Fier

Overvoltage Surge Protection
Last but not least, for the rare instances where there is an overvoltage spike (from a mains electricity surge or lightning strike for example), the AC iPurifier will automatically shut off and stop electricity from passing through your system. This should protect your valuable and highly-sensitive mains equipment from harm.

Click to expand...

How is it supposed to be able to do that if it's next to the outlet my electronics are in, rather than in between?

Headphoneus Supremus

Power conditioning as I understand it is a process of taking whatever comes out of the wall and trying to make it close to a perfect 60hz sine wave at the original voltage. This involves either filtering out harmonics and noise from the original power, or using the mains power for powering an active power supply which then synthesizes a whole new (presumably much more pure) 60hz "signal". This one seems to be a sort of filter, so if you already have a power conditioner it will make the power incrementally cleaner, but might also be considered redundant. If the noise in your power is already at -75dB or something and you pull it down another 40dB (in the best case) then you went from practically no noise, to practically no noise again. If your power is so bad as to require two power conditioners in series, you have big problems.

Click to expand...

Gawd the house I use to live in did have BIG problems! Non the less, I just upgraded my power conditioners to some with ANC so sounds like this one won't do me to much good! Still I like the simplicity of it

500+ Head-Fier

Power conditioning as I understand it is a process of taking whatever comes out of the wall and trying to make it close to a perfect 60hz sine wave at the original voltage. This involves either filtering out harmonics and noise from the original power, or using the mains power for powering an active power supply which then synthesizes a whole new (presumably much more pure) 60hz "signal". This one seems to be a sort of filter, so if you already have a power conditioner it will make the power incrementally cleaner, but might also be considered redundant. If the noise in your power is already at -75dB or something and you pull it down another 40dB (in the best case) then you went from practically no noise, to practically no noise again. If your power is so bad as to require two power conditioners in series, you have big problems.

Click to expand...

Active noise cancellation is suggesting that it is not filtering anything, but rather injecting its own noise in the form of the inverse of the deviation from a clean sign wave, hoping that the injected noise cancels out the already present noise, much like noise cancelling headphones do.

That means it first measures the current noise, then generates the opposite noise and injects it into the system, but by then the noise will have changed slightly, so some noise remains, even if it otherwise works perfectly. Again, much like noise cancelling headphones, which suck at cancelling sudden sounds.

I'm wondering whether this thing can effectively cause noise echo, where it's trying to cancel out noise it injected itself...

100+ Head-Fier

Head-Fier

I've seen those other similar plug in devices and always ignored them. The surge protector aspect of this one, though, I find interesting/odd. Quoting from the iFi product page:

"Last but not least, for the rare instances where there is an overvoltage spike (from a mains electricity surge or lightning strike for example), the AC iPurifier will automatically shut off and stop electricity from passing through your system."
​

Curious to know how it does this if it's not actually between the mains and the system. Also ... there doesn't seem to be a reset button as there is on many surge protectors.

Previously known as KMSV.

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So to use this product you need to get three? That is even if they even work. That's $300, I rather spend money on an online UPS (like this one), do a fan mod and you have regenerative power + all the advantages of an UPS.